The creation and support of Embodied Conversational Agents (ECAs) has been quite challenging, as features required might not be straight-forward to implement and to integrate in a single application. Furthermore, ECAs as desktop applications present drawbacks for both developers and users; the former have to develop for each device and operating system and the latter must install additional software, limiting their widespread use. In this paper we demonstrate how recent advances in web technologies show promising steps towards capable web-based ECAs, through some off-the-shelf technologies, in particular, the Web Speech API, Web Audio API, WebGL and Web Workers. We describe their integration into a simple fully functional web-based 3D ECA accessible from any modern device, with special attention to our novel work in the creation and support of the embodiment aspects.